Quarterly unit sales of the SPSS Manual, 1976:1-1982:4
#Quarterly unit sales of the SPSS Manual, Second Edition, from
#1976:1 through 1982:4.  (SPSS is a leading statistical computing
#package; the manual was actually sold through McGraw-Hill, Inc.)
   5292  6748 11499  4612  5511  8960  9859 14578  7386  7503 12575 12348  7999
   6963 12378 13008  9257  6043 16605  7615  9248  7138 15051 11628 12862  8207
  14912 14639
